Typically, gas turbine engines include a compressor for compressing air, a combustor for mixing the compressed air with fuel and igniting the mixture, and a turbine blade assembly for producing power. Compressed air is supplied from the compressor to the combustor through a plenum formed by a shell surrounding a plurality of transition channels. The compressed air is passed through an often crude duct system between the compressor and the combustor that is often riddled with inefficiencies that reduce the efficiency of the turbine engine. The duct system has been configured in this manner so that the transition channels may be cooled with the compressed air while the compressed air is flowing to the combustor. Flow of the cooling fluids within this plenum is often controlled with an axial diffusor that directs the compressed air through an opening between the axial diffusor and the transition channel. Radial diffusors have been used to redirect the compressed gases between adjacent transition channels in turbine engines in which the transition channels are spaced sufficiently to enable use of the radial diffusors. However, in turbine engines without the sufficient space between adjacent transitions channels, radial diffusors are not an available option. Conventional systems often restrict flow between the axial diffusors and the transition channels, thereby resulting in increased compressed air velocity and increased flow losses. Thus, in systems in which axial diffusors are used, a need exists for a more efficient fluid flow configuration.